The present invention relates to an expansion card. The invention relates also to a method in the manufacture of an expansion card. Moreover, the invention relates to an antenna structure which is arranged to be fitted in a wireless communication device card. Furthermore, the invention relates to an arrangement for a wireless communication device for setting an antenna structure and guiding it in different positions.
In wireless communication devices, such as mobile phones, antennas used for the transmission and reception of radio-frequency signals include e.g. a monopole antenna and a helix antenna, in a way known per se. The radio-frequency signals are transmitted between the radio part and the antenna of the wireless communication device by means of conventional wiring and connectors. The dimensioning of antennas depends e.g. on the frequency range of the radio-frequency signal to be used at the time. In view of the operation of the antenna, it is advantageous that it is placed in a free space outside a mobile station or a corresponding device. Thus, the antenna is located farther from components causing radio interference, such as integrated circuits (IC) and radio frequency (RF) circuits, and the structures of the device do not interfere with the radiation pattern of the antenna, wherein the reception of radio-frequency signals is more reliable, particularly in a weak signal field.
According to prior art, various electronic devices, such as portable personal computers (PC) are often equipped with an expansion card interface, to which a standardized expansion card can be connected. These expansion cards are intended to form a functional unit with the PC. The expansion cards may also contain radio parts of a wireless communication device with its antenna, wherein the PC can, by means of this wireless communication device card, communicate with other devices or with a communication network, e.g. the GSM network (Global System for Mobile Communication).
One known expansion card is the PC card complying with the PCMCIA standard (Personal Computer Memory Card International Association). The PCMCIA standard also defines the physical size of the PC card. The PC cards are fitted to be inserted fully inside the PC, but so-called extended PC cards can be longer than ordinary PC cards. These extended PC cards are placed partly outside the PC, wherein the thickness and design of the PC cards may vary in this part which typically also contains the antenna of the wireless communication device card.
One known wireless communication device card which comprises a transceiver with its antenna is the Nokia Cellular Card Phone, i.e. a card phone that can be connected to expansion card interfaces of types II and III of the PC card complying with the PCMCIA standard. One embodiment of the card phone of prior art is shown in FIG. 1, and the operation of the card phone is described in more detail e.g. in patent publication U.S. Pat. No. 5,809,115. The card phone in question can comply with e.g. the GSM standard, wherein the PC device to which the card phone is connected can be in a wireless data transmission connection with base stations of a PLMN network (Public Land Mobile Network) by means of radio waves. In the card phone, the antenna part containing the antenna is placed in the part of the card phone located outside the PC device, and the antenna part is integrated with the card part of the card phone which is placed inside the expansion card connection. Other known wireless communication device cards are presented in patent publication U.S. Pat. No. 5,628,055, wherein a separate turnable antenna can be connected to the end of the card, and in U.S. Pat. No. 5,361,061, wherein a foldable antenna is pivoted at the end of the extended card on its upper surface. One wireless communication device card is also disclosed in the patent publication WO 97/49194, in which a card can be equipped with a separate fixed antenna part or, by means of a wire, a separate elongated antenna.
Other known expansion cards include e.g. a so-called CompactFlash (CP) card complying with the CFA standard (Compact Flash Association). For example for these CP cards, there are also adapters of the size of the PCMCIA card, in which the CP card is placed for the PCMCIA Interface. Also known are expansion cards for a wireless local area network (WLAN). Other expansion cards include also a so-called Miniature Card, whose size is only 38 mmxc3x9733 mmxc3x973.5 mm, as well as a so-called SmartMedia card, whose size is only 45 mmxc3x9737 mmxc3x970.76 mm, and an MMC card (so-called MultiMediaCard), whose size is only 32 mmxc3x9724 mmxc3x971.4 mm.
One drawback in known communication device cards is the fact that during the use, particularly the antenna structure constitutes a part that protrudes from both the electronic device and the card. Moreover, the connections often comprise a protective cover to protect the expansion card, which must be kept open as the antenna structure extends outside the electronic device. The protruding parts of the antenna structure or of the card and protective covers may stick in something particularly during the transportation and use of the device, as well as they may damage the card or the antenna part. For this reason, the card must be detached after the use and be stored separately from the PC device for example during transportation; accordingly, a requirement for putting the device into working order is that the wireless communication device card is inserted back in its place.
It is an aim of the present invention to eliminate the above mentioned drawback and to present a considerable improvement to the prior art by means of a wireless communication device card according to the invention.
A wireless communication device card according to the invention, such as a card phone, has the considerable advantage that it can be made e.g. in the size of a PCMCIA card, wherein it fits fully inside e.g. the expansion card connection of a PC device. The wireless communication device card preferably constitutes an integrated unit with standardized dimensions, and thanks to a push in antenna, no protruding or separate carte will be formed in the structure of the card, wherein even an extended card will not comprise easily sticking or detachable elements.
The antenna structure of the invention can be placed, at least in its transportation position, fully inside the card, wherein the antenna structure to protected. Furthermore, it is an advantage of the spring operation that there is no need to provide the card or the antenna structure, particularly its end, with recesses, openings or extra parts for pulling the antenna out of the card, or to arrange closing devices or clamps for locking the antenna structure which would require space at the end of the card. Another advantage of the antenna structure is that its movement, thanks to the spring operation, can be arranged to be such that the antenna part is moved by its own force ready to its functional position at a correct distance from the device and from the card, wherein the user does not need to take care of pulling out the antenna part to this distance. Moreover, it is an advantage of the antenna structure that it can also be fitted in other wireless communication devices of prior art, such as mobile phones. As an integrated structure, the antenna structure can also be easily installed and changed.
The arrangement of the invention to control the different positions of the antenna structure makes it possible to couple the antenna structure to a wireless communication device, such as an expansion card, movably with a very simple and compact arrangement. A particular advantage is the thin construction, wherein the arrangement suits thin cards particularly well. An advantage of the arrangement is that it can be preferably applied for coupling antennas of different types movingly to a card. Thus, the arrangement can be coupled by means of intermediating parts e.g. to antenna parts placed fully outside the card and set in different positions, wherein the arrangement can be used to move the antenna part further from the card or to bring it closer to the card.
It is also an advantage that the presented arrangement leaves as much space as possible for the circuit board of the card and for the components placed thereon in the longitudinal direction and in the thickness direction of the card. A particular advantage is also achieved in that the end of the card, which is visible in the connection, has as wide an area as possible for connectors, the antenna part only taking space for its cross-section.
The wireless communication device card according to the invention does not need to be removed from the PC device for the time of transportation. Thus, the start-up of the PC device, the setting up of the radio connection, and the start of wireless communication become faster. At the same time also the acts of inserting and removing the card in and from the expansion card connection are decreased, wherein the wear of the connection is reduced, and malfunctions are decreased.
It is a particular advantage of the invention that the antenna is placed in a free area outside the device when it protrudes in its functional position. Thus, the antenna is located farther from the components causing radio interference, such as the processor of a computer. The influence of electromagnetic interference caused by the components decreases as the distance increases. It is possible that a sufficiently strong antenna structure in its functional position can be used for pulling out the card from the expansion card connection, wherein the device or the card do not need to be equipped with means or mechanisms facilitating the pulling out.